The objective for the period covered is to obtain purified rod and cone pigments from chicken retinas, find their composition, and study the light dependence of their properties and, in addition, to prepare purified photoreceptors from both cell types. BIBLIOGRAPHIC REFERENCES: Fager, R.S., Kandel, M., Heppner, T., and Abrahamson, E.W. Sodium borohydride reduction of iodopsin, Vision Research 15: 741 (1975). Salter, M., Gentilecore, P., Fager, R.S., Kuntz, G.P.P., Menter, J., Abrahamson, E.W. and West, S.S. Behavior of dye-mucopolysaccharide complexes-spectroscopic-studies of the system chondroitan sulfate A-acridine orange. Photochem. and Photobiol. 20: 59, (1974).